Calcifediol boosts efficacy of ChAdOx1 nCoV-19 vaccine by upregulating genes promoting memory T cell responses

The ChAdOx1 nCoV-19 (COVISHIELD) vaccine has emerged as a pivotal tool in the global fight against the COVID-19 pandemic. In our previous study eligible subjects were supplemented with calcifediol, a direct precursor to the biologically active form of vitamin D, calcitriol with an objective to enhance the immunogenicity of the COVISHIELD vaccine. Herein we investigated the effects of calcifediol supplementation on gene expression profiles in individuals who received the COVISHIELD vaccine. Peripheral blood mononuclear cells were isolated from vaccinated individuals with and without calcifediol supplementation at baseline, 3rd and 6th month, and the gene expression profiles were analyzed using high-throughput sequencing. The results revealed distinct patterns of gene expression associated with calcifediol supplementation, suggesting potential molecular mechanisms underlying the beneficial effects of calcifediol in improving the efficacy of COVISHIELD vaccine via augmentation of T cell activation, proliferation and T cell memory responses. Additionally, there was upregulation of NOD like receptor, JAK/STAT and TGF beta signaling pathways. Calcifediol supplementation in vaccinated individuals also downregulated the pathways related to the Coronavirus disease. Taken together, our findings provide valuable insights into the interplay between vitamin D receptor (VDR) signaling and vaccine-induced immune responses and offer another approach in improving vaccination induced antiviral responses.

The *25(OH)D and #Calcitriol levels at baseline versus 1 st month were measured in plasma of calcifediol supplemented subjects.The data is shown as mean±standard deviation (SD).
Supplementary Table 3. Monotonous upregulation of vitamin D response elements (VDRE) genes at the 3rd and 6th month in the calcifediol supplemented (treated) group.

Gene ID_Gene Name
Supplementary Table 4: Complete List of Biological processes found differentially upregulated upon Calcifediol supplementation (Treated 6 months versus treated baseline). of small GTPase mediated signal transduction Ubiquitin-dependent protein catabolic process Peptidyl-serine phosphorylation RNA splicing COPII-coated vesicle cargo loading Regulation of DNA-templated transcription Protein autophosphorylation Regulation of cell cycle Double-strand break repair Alternative mRNA splicing, via spliceosome miRNA processing miRNA-mediated gene silencing by inhibition of translation Positive regulation of I-kappa B kinase/NF-kappa B signaling Clathrin coat assembly Protein localization to centrosome Protein polyubiquitination Proteasome-mediated ubiquitin-dependent protein catabolic process mRNA export from nucleus Negative regulation of translation Regulation of alternative mRNA splicing, via spliceosome Mitotic spindle assembly Positive regulation of NF-kappa B transcription factor activity BMP signaling pathway Intrinsic apoptotic signaling pathway Double-strand break repair via homologous recombination DNA repair Regulation of signal transduction by p53 class mediator transition of mitotic cell cycle Positive regulation of nuclear-transcribed mRNA catabolic process, deadenylation-dependent decay Cytokine-mediated signaling pathway mRNA transcription by RNA polymerase II Protein stabilization DNA replication mRNA splicing, via spliceosome Transcription initiation-coupled chromatin remodeling RNA polymerase II preinitiation complex assembly Regulation of mRNA splicing, via spliceosome Retrograde transport, endosome to Golgi Mismatch repair Negative regulation of NF-kappa B transcription factor Positive regulation of transcription initiation by RNA polymerase II Positive regulation of cytokinesis Actin cytoskeleton organization Regulation of cellular response to heat Histone H3 deacetylation Positive regulation of blood vessel endothelial cell migration Positive regulation of phosphatidylinositol 3-kinase signaling Positive regulation of nuclear-transcribed mRNA poly(A) tail shortening Protein sumoylation Positive regulation of extrinsic apoptotic signaling pathway Replication fork processing Mitotic G2 DNA damage checkpoint signaling Positive regulation of telomere maintenance via telomerase Cellular response to UV Positive regulation of canonical Wnt signaling pathway growth factor receptor signaling pathway Positive regulation of DNA-binding transcription factor activity Regulation of heart rate by cardiac conduction Mitotic spindle organization Intrinsic apoptotic signaling pathway in response to DNA damage by p53 class mediator Phosphatidylinositol 3-kinase signaling Cell adhesion Double-strand break repair via nonhomologous end joining Integrin-mediated signaling pathway Protein import into nucleus Positive regulation of mRNA catabolic process Negative regulation of proteasomal ubiquitin-dependent protein catabolic process Positive regulation of miRNA-mediated gene silencing Mitotic spindle assembly checkpoint signaling Negative regulation of anoikis Negative regulation of stress fiber assembly Negative regulation of viral genome replication Positive regulation of isotype switching Protein K63miRNA transcription Stimulatory C-type lectin receptor signaling pathway Response to lipopolysaccharide Negative regulation of protein ubiquitination Cellular response to amino acid starvation Response to estrogen Regulation of embryonic development Cellular glucose homeostasis Ubiquitin-dependent ERAD pathway Regulation of DNA strand elongation Positive regulation of protein localization to plasma membrane Nuclear-transcribed mRNA catabolic process, nonsense-mediated decay Golgi to endosome transport Cellular response to starvation Notch signaling pathway 3'-UTR-mediated mRNA destabilization Transforming growth factor beta receptor signaling pathway Positive regulation of histone H3-K4 methylation B cell receptor signaling pathway Regulation of mitotic cell cycle Cholesterol biosynthetic process Cellular response to gamma radiation Positive regulation of apoptotic process Positive regulation of SMAD protein signal transduction Cell adhesion mediated by integrin Ion transmembrane transport Transcription initiation at RNA polymerase II promoter Positive regulation of epithelial cell migration Regulation of chromosome organization Positive regulation of epithelial to mesenchymal transition mitotic cell cycle Monoubiquitinated histone H2A deubiquitination

Table 1 :
The number of subjects exposed to SARS-CoV-2 and subjects with prior COVID-19 disease

Table 2 :
Calcitriol and Vitamin D levels of Calcifediol supplemented subjects